Based in the industrial heart of Hamilton, Latham Steel has built a strong reputation as a trusted manufacturer and supplier, specializing in robust materials for demanding environments. Our expertise shines with Alloy Steel P91 Pipes, which we supply to projects across New Zealand and beyond. We understand that the integrity of your work depends on the quality of your materials, which is why we stand behind the exceptional performance of P91, ensuring you receive a product engineered for reliability and long-term service in the most challenging applications.
The strength of Alloy Steel P91 comes from a carefully balanced composition, primarily chromium and molybdenum, with important additions of vanadium and niobium. This specific recipe gives these pipes their remarkable mechanical properties, including very high tensile strength and excellent resistance to creep, which is the slow deformation that can happen under constant high heat and pressure. This combination allows P91 to perform reliably in extreme temperature environments where ordinary steel would quickly fail, making it a durable and efficient choice.
| Type | Seamless / ERW / Welded / Fabricated |
| Standard | ASTM A335 P91, SA335 P91 (with IBR Test Certificate) |
| Size | 1/2” NB to 36” NB |
| Length | Standard Double & In Cut length also. |
| Schedules | SCH 40, SCH 80, SCH 160, SCH XS, SCH XXS, All Schedules |
| Tolerance | Cold drawn pipe: +/-0.1mm
Cold rolled pipe: +/-0.05mm |
| Application | Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service |
| End | Plain End, Beveled End, Treaded |
| Craft | Cold rolled and Cold drawn |
| available in Form of | Round, Square, Rectangular, Hydraulic Etc. |
| Origin | European, Japanese, Korean, US, Russian, New Zealandn (Strictly No Chinese Material) |
| Specialized in | Large Diameter ASTM A335 P91 Pipe |
| Additional Testing | NACE MR 0175, NACE TM0177, NACE TM0284, HIC TEST, SSC TEST, H2 SERVICE, IBR, etc. |
| Thickness | 3-12mm |
| Alloy Steel P91 | C | Cr | Mn | Mo | P | S | Si |
| 0.08-0.12 | 8.00 – 9.50 | 0.30-0.60 | 0.85 – 1.05 | 0.020 max | 0.010 max | 0.20 -0.50 |
| Tensile Strength, MPa | Yield Strength, MPa | Elongation |
| 585 min | 415 min | 20 min |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
Latham Steel is a major manufacturer and a supplier of premium Alloy Steel P91 pipe in Hamilton, the New Zealand. With specialization in steel solutions, we offer a variety of products including carbon steel, alloy steel, light steel and galvanized steel. Our wide bearing has pipes, pipes, flanges, pipe fittings, forged fittings, sheets and plates. We are famous for our reliable distribution and extraordinary customer service, and are committed to offering high quality steel materials that ensure durability and better performance in different industrial applications. We are committed to skill, and we are your reliable partners for all steel requirements.
| ASTM | ASME | Equivalent material | JIS G 3458 | UNS | BS | DIN | ISO | ABS | NK | LRS |
|---|---|---|---|---|---|---|---|---|---|---|
| A335 P91 | SA335 P91 | T91, K90901, X10CrMoVNb9-1, 1.4903 | K91560 |
| O.D.(mm) x Thickness(mm) | O.D(mm) x Thickness(mm) | O.D(mm) x Thickness(mm) |
|---|---|---|
| 38.1 x 3.2 | 57.0 x 4.9 | 76.2 x 4.0 |
| 38.1 x 4.0 | 57.0 x 6.3 | 76.2 x 5.0 |
| 38.1 x 6.3 | 57.0 x 7.9 | 76.2 x 6.3 |
| 42.4 x 3.2 | 60.3 x 3.2 | 82.5 x 4.5 |
| 42.4 x 4.0 | 60.3 x 3.6 | 88.9 x 3.2 |
| 44.5 x 3.2 | 60.3 x 5.0 | 88.9 x 3.6 |
| 44.5 x 6.3 | 63.5 x 3.2 | 88.9 x 4.0 |
| 48.3 x 3.2 | 63.5 x 3.6 | 101.6 x 3.6 |
| 48.3 x 3.6 | 63.5 x 4.0 | 101.6 x 4.5 |
| 50.8 x 4.5 | 63.5 x 6.3 | 101.6 x 6.3 |
| 51.0 x 3.2 | 63.5 x 7.9 | 114.3 x 3.6 |
| 51.0 x 3.6 | 70.0 x 3.2 | 114.3 x 5.0 |
| 51.0 x 6.3 | 70.0 x 3.6 | 139.7 x 4.0 |
| 57.0 x 3.2 | 70.0 x 6.3 | 139.7 x 5.0 |
| 57.0 x 3.6 | 76.2 x 3.6 | 139.7 x 6.3 |
| Size NPS | Pipe O.D. | Wall Thickness | Pipe I.D. | Weight per Foot | Standard to XXHY | Schedule Pipe # | Section Modulus | Gallon Capacity Per Linear Foot |
| 1/2 | 0.84 | 0.109 | 0.622 | 0.85 | STD | 40 | .0407 | .0158 |
| 0.147 | 0.546 | 1.09 | XHY | 80 | .0478 | .0122 | ||
| 0.188 | 0.464 | 1.31 | 160 | .0528 | .0088 | |||
| 0.294 | 0.252 | 1.72 | XXHY | .0577 | .0026 | |||
| 3/4 | 1.05 | 0.113 | 0.824 | 1.13 | STD | 40 | .0705 | .0277 |
| 0.154 | 0.742 | 1.48 | XHY | 80 | .0853 | .0225 | ||
| 0.219 | 0.612 | 1.95 | 160 | .1006 | .0153 | |||
| 0.308 | 0.434 | 2.44 | XXHY | .1103 | .0077 | |||
| 1 | 1.315 | 0.133 | 1.049 | 1.68 | STD | 40 | .1328 | .0449 |
| 0.179 | 0.957 | 2.17 | XHY | 80 | .1606 | .0374 | ||
| 0.250 | 0.815 | 2.85 | 160 | .1904 | .0271 | |||
| 0.358 | 0.599 | 3.66 | XXHY | .2136 | .0146 | |||
| 1 1/4 | 1.66 | 0.140 | 1.380 | 2.27 | STD | 40 | .2346 | .0777 |
| 0.191 | 1.278 | 3.00 | XHY | 80 | .2913 | .0666 | ||
| 0.250 | 1.160 | 3.77 | 160 | .3421 | .0549 | |||
| 0.382 | 0.896 | 5.22 | .4110 | .0328 | ||||
| 1 1/2 | 1.90 | 0.145 | 1.610 | 2.72 | STD | 40 | .3262 | .1058 |
| 0.200 | 1.500 | 3.63 | XHY | 80 | .4118 | .0918 | ||
| 0.281 | 1.338 | 4.86 | 160 | .5079 | .0730 | |||
| 0.400 | 1.100 | 6.41 | .5977 | .0494 | ||||
| 2 | 2.375 | 0.109 | 2.157 | 2.64 | 10 | .4205 | .1898 | |
| 0.154 | 2.067 | 3.66 | STD | 40 | .5606 | .1743 | ||
| 0.218 | 1.939 | 5.03 | XHY | 80 | .7309 | .1534 | ||
| 0.250 | 1.875 | 5.68 | .8045 | .1434 | ||||
| 0.281 | 1.813 | 6.29 | .8666 | .1344 | ||||
| 0.344 | 1.687 | 7.47 | 160 | .9806 | .1161 | |||
| 0.436 | 1.503 | 9.04 | XXHY | 1.1043 | .0922 | |||
| 2 1/2 | 2.875 | 0.120 | 2.635 | 3.53 | 10 | .6870 | .2833 | |
| 0.203 | 2.469 | 5.80 | STD. | 40 | 1.0640 | .2487 | ||
| 0.216 | 2.443 | 6.14 | 1.1169 | .2435 | ||||
| 0.250 | 2.375 | 7.02 | 1.2468 | .2301 | ||||
| 0.276 | 2.323 | 7.67 | XHY | 80 | 1.3386 | .2202 | ||
| 0.375 | 2.125 | 10.02 | 160 | 1.6371 | .1842 | |||
| 0.552 | 1.771 | 13.71 | XXXHY | 1.9971 | .1280 | |||
| 3 | 3.50 | 0.120 | 3.260 | 4.34 | 1.0411 | .4336 | ||
| 0.156 | 3.188 | 5.58 | 1.3122 | .4147 | ||||
| 0.172 | 3.156 | 6.12 | 1.4265 | .4064 | ||||
| 0.188 | 3.124 | 6.66 | 1.5342 | .3984 | ||||
| 0.216 | 3.068 | 7.58 | STD. | 40 | 1.7241 | .3840 | ||
| 0.250 | 3.000 | 8.69 | 1.9372 | .3672 | ||||
| 0.281 | 2.938 | 9.67 | 2.1207 | .3521 | ||||
| 0.300 | 2.900 | 10.26 | XHY | 80 | 2.2253 | .3431 | ||
| 0.438 | 2.624 | 14.34 | 160 | 2.8774 | .2811 | |||
| 0.600 | 2.300 | 18.6 | XXHY | 3.4243 | .2158 | |||
| 3 1/2 | 4.0 | 0.120 | 3.760 | 4.98 | 10 | 1.3776 | .5768 | |
| 0.226 | 3.548 | 9.12 | STD. | 140 | 2.3939 | .5136 | ||
| 0.250 | 3.500 | 10.02 | 2.6001 | .4998 | ||||
| 0.281 | 3.438 | 11.17 | 2.8562 | .4821 | ||||
| 0.318 | 3.364 | 12.52 | XHY | 80 | 3.1400 | .4617 | ||
| 0.636 | 2..728 | 22.87 | XXHY | 4.8795 | .3085 | |||
| 4 | 4.5 | 0.120 | 4.260 | 5.62 | 10 | 1.7612 | .7404 | |
| 0.156 | 4.188 | 7.24 | 2.2354 | .7156 | ||||
| 0.188 | 4.124 | 8.67 | 2.6296 | .6942 | ||||
| 0.203 | 4.094 | 9.32 | 2.8173 | .6838 | ||||
| 0.219 | 4.062 | 10.02 | 3.0184 | .6725 | ||||
| 0.237 | 4.026 | 10.80 | STD. | 40 | 3.2145 | .6613 | ||
| 0.250 | 4.000 | 11.36 | 3.3611 | .6528 | ||||
| 0.281 | 3.938 | 12.67 | 60 | 3.7021 | .6326 | |||
| 0.312 | 3.876 | 13.97 | 4.0273 | .6126 | ||||
| 0.337 | 3.826 | 15.00 | XHY | 80 | 4.2713 | .5972 | ||
| 0.438 | 3.624 | 19.02 | 120 | 5.1790 | .5361 | |||
| 0.531 | 3.438 | 22.53 | 160 | 5.8997 | .4822 | |||
| 0.674 | 3.152 | 27.57 | XXHY | 6.7927 | .4054 | |||
| 5 | 5.563 | 0.188 | 5.187 | 10.80 | 4.1161 | 1.0979 | ||
| 0.219 | 5.125 | 12.51 | 4.7279 | 1.0716 | ||||
| 0.258 | 5.047 | 14.63 | STD. | 40 | 5.4500 | 1.0391 | ||
| 0.281 | 5.001 | 15.87 | 5.8644 | 1.0204 | ||||
| 0.312 | 4.939 | 17.51 | 6.4074 | .99647 | ||||
| 0.344 | 4.875 | 19.19 | 6.9358 | .9696 | ||||
| 0.375 | 4.813 | 20.80 | XHY | 80 | 7.4300 | .9449 | ||
| 0.500 | 4.563 | 27.06 | 120 | 9.2534 | .8495 | |||
| 0.625 | 4.313 | 32.99 | 160 | 10.7976 | .7590 | |||
| 0.750 | 4.063 | 38.59 | XXHY | 12.0954 | .6734 | |||
| 6 | 6.625 | 0.109 | 6.407 | 7.59 | 5 | 3.5769 | 1.6748 | |
| 0.134 | 6.357 | 9.30 | 10 | 4.3475 | 1.6488 | |||
| 0.156 | 6.313 | 10.79 | 5.0107 | 1.6260 | ||||
| 0.188 | 6.249 | 12.94 | 5.9351 | 1.5937 | ||||
| 0.203 | 6.219 | 13.94 | 6.3804 | 1.5780 | ||||
| 0.219 | 6.187 | 15.00 | 6.8261 | 1.5620 | ||||
| 0.250 | 6.125 | 17.04 | 7.6905 | 1.5306 | ||||
| 0.280 | 6.065 | 18.99 | STD. | 40 | 8.4958 | 1.5008 | ||
| 0.312 | 6.001 | 21.06 | 9.3416 | 1.4688 | ||||
| 0.344 | 5.937 | 23.10 | 10.111 | 1.4391 | ||||
| 0.375 | 5.875 | 25.05 | 10.893 | 1.4082 | ||||
| 0.432 | 5.761 | 28.60 | XHY | 80 | 12.224 | 1.3541 | ||
| 0.500 | 5.625 | 32.74 | 13.711 | 1.2909 | ||||
| 0.562 | 5.501 | 36.43 | 120 | 14.9806 | 1.2346 | |||
| 0.625 | 5.375 | 40.09 | 16.1821 | 1.1787 | ||||
| 0.719 | 5.187 | 45.39 | 160 | 17.8243 | 1.0977 | |||
| 0.864 | 4.897 | 53.21 | XXHY | 20.025 | .9784 | |||
| 1.000 | 4.625 | 60.13 | 21.7719 | .8727 | ||||
| 1.125 | 4.375 | 66.14 | 23.1237 | .7809 |
You’ll typically find Alloy Steel P91 Pipes hard at work in critical high-temperature systems, forming the backbone of modern power generation plants, including fossil fuel and renewable energy facilities. Their ability to withstand immense pressure and heat also makes them ideal for refineries and petrochemical operations. Essentially, any application that demands a pipe to reliably carry superheated steam or aggressive process fluids over long periods benefits from the superior durability that P91 provides, helping to ensure operational safety and reduce maintenance needs.
Latham Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Hamilton, New Zealand.
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